CATALYTIC REACTOR COMPRISING FIRST AND SECONDARY FLOW CHANNELS ARRANGED ALTERNATELY

摘要

A compact catalytic reactor (20) comprises a channel for a rapid reaction having an inlet (26) for a gas mixture to undergo the reaction. The channel is provided with two different catalyst structures (32, 34), a first catalyst structure (32) in the vicinity of the inlet (26) and a second catalyst structure (34) further from the inlet, such that a gas mixture supplied to the inlet flows past them both. The first catalyst structure (32) has little catalytic activity for the rapid reaction, whereas the second catalyst structure (34) has catalytic activity for the rapid reaction. This is applicable to combustion of gas mixtures containing hydrogen, for which the first catalyst structure (32) may comprise uncoated oxidised aluminium-containing ferritic steel, while the second catalyst structure (34) may incorporate Pt and/or Pd in an alumina support. Exhaust gases may also be recycled to the inlet (26) to inhibit combustion.